Plate and method of treating the same



Sept; 22., 1924. 1,509,495

J. SLEPIAN PLATE AND METHOD OF TREATING THE SAME Original Filed April 1,1922 Fig. 5.

WITNESSES: INVENTOR J hl am W .1922, Plate and a, method Patented Sept.23, 1924.

UNITED stares PATENT omen.

JOSEPH LEPIAN, OF SWISSV'ALE, PENNSYLVANIA, ASSIG-NOIL T0 WESTINGHOUSEELECTRIC & MANUFACTURING COMPANY, A

CORPORATI ON OF? PENNSYLVANIA.

PLATE AND METHOD OF TREATING THE SAME.

Application filed April 1,, 1922,8eria1 No. 548,637.

and Methods of Treating the Same,'of which the following is aspecification.

This invention relates to lightning arresters, more particularly to mynew type of lightning arrester which consists fundamentally of stackedplates or disks of high resistance material connected in a suitablemanner to an electrical system to be protected.

It is desirable in many cases that the points of contact of the adjacentplates be of very high resistance and I have, therefore, devised astructure of plate and ,a method of making the same which provides suchhigh resistance contact points. This invention is described in my 00ending application, Serial No. 548,638, fi

ed 'April 1, of treating the same (Case 9674).

In the aforesaid application, I have described a method which consistsin stacking plates of high resistance material, placing a relativelysmall number of thin mica' washers therebetween, connecting the stackedplates t'oan electrical circuit and passing a current therethrough toheat and partially oxidize the surfaces of the plates and thus increasethe resistance of the contact points thereof. I

In my present invention, I have succeeded in accomplishing the sameresult in a some- What difierent and simplified manner. I first providea rod of resistance material which generally contains graphite orsimilar carbonaceous material, carborundum or the like and kaolin. Therod, at a relatively high temperature, is exposed to the air, causingsuperficial oxidation of the surface thereof, increasing the resistanceof said surface, and rendering the same harder than the body of the rod.The rod is then out transversely of its axis and the plates thus formedare stacked and electrodes applied to the end plates. A current ispassed through the stack of plates for a length of time suflicient toheat and partially oxidize the contact points and thus increase theirresistance.

the proper Renewed July 29, 1924.

In the accompanying drawing constituting a part hereof and in which likereference characters designate like parts,

'Fig. '1 is a plan view of a rod of resistance material which has beenexposed to the air while in a heated condition;

' ig. 2-is a vertical crosssectional view thereof taken along the lineIIII of Fig. l

Fig. 3 is a plan view clamped between electrodes preparatory to the nextstep of the treatment Fig. 4 is a vertical cross-sectional view thereoftaken along the line IV-IV of Fi 3; c ig. 5 is a plate and Fig. 6 is avertical cross-sectional view thereof taken along the line VI+VI of Fig.5 showing the high resistance contact points exaggerated in size to moreclearly illustrate a feature of my invention.

- Referring particularly to Figs. 1 and 2, I

provide a rod 1 of resistor material of any suitable type which iscapable of partially oxidizing and is adapted to have its resistancematerially increased thereby. Generally, I prepare a mixture ofgraphite, carborundum, and kaolin which are mixed to consistency withwater. The composition is compressed in suitablemolds of the desiredform and then fired in a furnace. The hot rod is removed from thefurnace and exposed to the atmosphere for a relatively short time,whereby the surface 2 of the .rod becomes oxidized owing to theoxidation of the carbon of the composition, resulting in a surface ofhigh resistance and relatively great hardness.

The rod is then out transversely of its longitudinal axis providingplates 3 which are stacked as shown in Figs. 3 and 4. Electrodes 4 and 5are respectivel laced of a stack of plates plan view of "a" completed onthe end plates of the stack an t e as-- count of this phenomenon, thecontact points 6 and? of the faces of the plates do not bear anymaterial pressure during the operation and, therefore, any danger of thehot oxidized, high resistance contact points collapsing is avoided.

It will be obvious from the above description of my invention that I amenabled to provide plates of high resistance materials having theexposed surfaces and the contact points of the faces thereof of stillhigher resistance in a very simple manner. My method lends itself toquantity production and the resulting plates are uniform in theircomposition.

Although I have described a specific embodiment of my invention, it willbe obvious to those skilled inthe art that various changes in thedetails of manipulation of my process may be made withoutdeparting fromthe instance, may utilize a different-composition of material than thatwhich I preferably use and the treatmentv thereof may be varied toprovide the desired results. Instead of exposing the rod of resistancematerial to the air to increase the resistance of the surface thereof, Imay provide a coating on the rod of hi her resistance material or Imayoxidize the surface of said rod .in any other suitable manner.

I claim as my invention:

1. A plate of resistance material, the edges thereof having a higherresistance than the body..

2. A plate of resistance material, the edges and portions of the facesthereof having a higher resistance than the body.

3. A plate of resistance material including a carbonaceous substance,the edges aheireof having a higher resistance than the 4. A plate ofresistance material including a. carbonaceous substance, the edges andportions of the faces thereof having a higher resistance than the body.

5. A method of treating plates of resistance materialwhich comprisesproviding a high resistance portion on said plates, p acing said platesin contact and heating the same to raise the resistance of portions ofthe faces of said plates.

6. A method of treating plates of resistance material which comprisesproviding a high resistance portion on said. plates, plac- Iprinciplesherein set forth. For

ance material which comprises providing :1

high resistance edge on said plates,placing said plates in contact andheating the same by passing a current therethrough to raise theresistance of portions of the faces of said plates.

9. A m'fithod of .treating plates of resistance material which comprisesproviding a high resistance portion on said plates by oxidizing thesame, placing said plates in contact and heating the same to raise there-v sistance of portions of the faces of said plates.

10. A method of treating plates of resistance material which comprisesproviding a high resistance edge onsaid plates by 0xi-' dizing the same,placing said plates in contact and heating the-same to raise theresistance of portions. of the faces of said plates.

11. A method of making plates of resistance material which comprisesproviding'a rod of resistance material, treating the same to provide ahigh resistance surface thereon, cutting the same transversely,assembling the plates so formed and heating the same toraise theresistance of the portions of faces of said plates.

12. A method of making plates of resistance material which comprises.providing a rod of resistance material, treating the same to provide ahigh resistance surface thereon, cutting the same transversely of thelongitudinal axis thereof, assembling the plates so formed and heatingthe same by passin an electric current therethrough to raise t eresistance of portions of the faces of said plates.

13." A method of making plates of resistance material'which comprisesproviding a rod of resistance material, oxidizing the same to provide ahigh resistance surface thereon, cutting the same transversely of thelongitudinal axis thereof, assembling the plates so formed and heatingthe same to raise the resistance of portions of the faces of saidplates. a

14. A method of making plates of resistanc'emateriahwhich comprisesproviding a rod of resistance mate ial, oxidizing the same to provide ahigh resistance surface thereon, cutting the same transversely of thelongitudinal axis thereof, assembling the plates so formed and heatingthe same by passing an electric current therethrough to raise theresistance of portions of the faces h h of said plates.

15. A method of treatingplates of resistance material which comprisesproviding a. h

high resistance portion on said plates,

ing said plates in contact so that said p are maintained in rigidrelation by 'said high resistance portion and heating the lacsame toraise the resistance of portions of 111 h the faces of said plates.

16: A method of treating plates of resistance material which comprisesproviding 9. hi h high resistance portion on said plates, lacb ing saidplates in contact are maintained in rigid relation by said f resistanceportion and the high -heatin same through to raise the resistance ofportions of the faces of said plates.

17. A method of treating plates of resistby passing an electric currentt ere-' ance material which comprises providing a said plates,

y said igh resistance edge and heating the same to raise the resistanceof portions of the faces of said plates.

18. A method of treating plates of resistance material which comprisesprovidin a 'g resistance edge on JOSEPH SLEPIAN.

